Self-repairing macromolecular materials have been actively researched in recent years; however, gels formed by crosslinking through general covalent bonding had a problem that if the bond was cut, bonding back to the original state was impossible, and thus self-repairing was difficult.
On the other hand, examples of self-repairing materials formed by non-covalent bonding, which is reversible bonding, include those formed by hydrogen bonding, ionic interaction, aromatic π-π interaction, bonding using metal complex formation and coordinate bonding, dynamic covalent bonding using radical formation in which binding and dissociation easily occur, or the like (PTL 1); however, all of them have insufficient bonding force. Moreover, rebinding occurs between non-cut parts. Thus, there was a problem in terms of shape memory properties.
In contrast, PTL 2 teaches that self-repairing properties and shape memory properties due to host-guest interactions are obtained from a gel comprising a host group-containing monomer, a guest group-containing monomer, and an acrylic monomer by dissolving the host group-containing monomer, the guest group-containing monomer, and the acrylic monomer in an aqueous solvent, and then copolymerizing the monomers.